Melbourne21.1 Surface water allocation announcements

Supporting Information

The volume recognised in the water accounting statements (19,521 ML) represents the volume of water announced for high-reliability water shares and low-reliability water shares in the Melbourne region during the 2010–11 year. Allocations are made according to Southern Rural Water's
Werribee & Bacchus Marsh Allocation Method.

Allocations were relatively high in the Melbourne region during the 2010–11 year due to the wet conditions across the region. The following table shows the breakdown of allocations made in the Melbourne region during the 2010–11 year.

Allocation announcements for high-reliability and low-reliability water shares in the Melbourne region during the 2010–11 year

Class

Location

Entitlement volume (ML)

Allocation(% of entitlement)

Allocation volume (ML)

High-reliability water shares

Werribee Irrigation District

10,040

100

10,040

Werribee River

907

100

907

Bacchus Marsh Irrigation District

3,880

100

3,880

Lake Merrimu direct access

190

100

190

Bacchus Marsh other

521

100

521

High-reliability water shares total

15,538

100

15,538

Low-reliability water shares

Werribee Irrigation District

4,777

55

2,627

Werribee River

435

55

239

Bacchus Marsh Irrigation District

2,030

55

1,117

Low reliability water shares total

7,242

55

3,983

Total all water shares

22,780

86

19,521

The following table shows the breakdown of allocation announcements by month. High reliability water shares started at 8% in July 2010, and increased to 30% in August following a wet period. Wet conditions prevailed through September and October, and allocations for high reliability water shares increased to 63% and 70% respectively. Significant rainfall late in November resulted in allocations reaching 100%. This was the highest allocation since 2001–02. At the same time during the 2009–10 year, allocations were 6% of high reliability water shares.

Low reliability water shares did not receive an allocation announcement until high reliability shares reached 100% in November 2010 (as per the
Werribee & Bacchus Marsh Allocation Method). The initial announcement of 10% in November was followed by an increase to 25% in December, and another increase to 45% in January 2011. A further five percent increase in February and another five percent increase in April saw the total allocation rise to 55% for the year.